Death Rattle?

[Harry]

Now that the cold mornings have returned so has the 'death ratlle' coming from the engine area....but worse than ever.

It happens on start up and continues until the engine has warmed up properly...then dissapears. Only happens on first start up of the day and sounds like someone has dropped a bag of loose nails into the engine bay.

Any ideas folks?

Van has now reached 238,000km and just completed a 300 mile round trip this weekend without a murmer (apart from the above)

H

[haydn callow]

Sounds to me like a perfectly normal "good old" diesel engine to me....Must be pretty worn but even new ones are a bit ratteley.

[helen&tony]

Hi
Minor rattle...tappets....Tinkly rattle, under slight acceleration maybe small ends....grumbly rattle under load...big ends. Try handbrake on , foot on brake, and give a little throttle, and see if the noise changes in any way.....hot and cold.
Cheers
Helen

[bigdaddycain]

Hi Harry, are you still running veg oil? A high ratio of veggy isn't desireable on colder mornings with cold engine.

Do you find that the rattle increases in volume when revved? Try letting the bongo warm up for a few moments (on tickover)whilst you are getting yourself together for the journey.

Do you know the viscosity of engine oil you are using?

[francophile1947]

Agree with BDC. Mine "pinks" for a short time on a cold morning, when running on 50/50 veg oil/diesel mix.

[Harry]

Rattle rate increases with revs.

Ratio of Derv/Veg oil does not seem to make a difference.

Rattle does not differentiate between being stationary and moving

Engine oil is castrol GTX diesel (don't know the viscosity)

Rattle diminishes as engine warms up and dissapears after about 2-3 minutes.

Thank you all for your input so far.

H

[mikeonb4c]

Does the oil pressure warning light go off promptly?

Is there any likelihood that - over time - using veg oil could gum up the piston / oil scraper rings. Would that have any relevance?

[francophile1947]

Still sounds like pinking to me - just like a bag of nails in the cylinders when accelerating

[bigdaddycain]

It could just be piston slap then harry,the pistons can expand just enough when heat gets into them to take up the "slack" in the cylinder bores,which consequently "quitens" the engine,the oil is running around more freely too as the oil gets thinner as it warms,this increases the lubrication.

Have you any other symptoms harry? Excessive smoke on start -up? ( i get a bit of blue smoke first thing).

[Harry]

Sometimes there is a delay in the oil warning light going out when starting from cold until the engine is revved then it immediately goes out and stays out.

Engine oil level checked most days and has only been topped up once in past year.

No smoke whatsoever even when engine revved hard.

Emission test on recent MOT was well within limits.

I don't know what 'pinking' means.

H

[haydn callow]

Pinking is another word for Pre ignition regarding a petrol engine. Deisels run hotter so they are looser and as they expand heating up, go a bit tighter.
I THINK...I am not a expert at anything

[mikeonb4c]

Hmmm - could we have gummy ring syndrome leading to piston slap until warmth and slapping ( ) eases things

[dandywarhol]

Thinking outside the box for a minute (doncha just hate that term?) try loading the steering to PART lock and holding it there when it's rattling - it might be the PAS pump noisy when the fluid is cold................

[scanner]

Pinking is another word for Pre ignition regarding a petrol engine. Deisels run hotter so they are looser and as they expand heating up, go a bit tighter.
I THINK...I am not a expert at anything

Are you trying to tell us you are green on some subjects.

[bigdaddycain]

Pinking is another word for Pre ignition regarding a petrol engine. Deisels run hotter so they are looser and as they expand heating up, go a bit tighter.
I THINK...I am not a expert at anything

I'm no expert at anything either, but i thought diesels ran colder because of their slower revving nature? Like i said, i'm no expert....